Across
1
Line segment connecting two circle points
3
Exact correspondence on both sides
4
Distance from center to edge of circle
5
Number with digits after a point
6
Math using letters for unknown values
8
Closed shape with straight sides
Down
2
Number divisible only by 1 and itself
3
Rectangle with four equal sides
4
Comparison of two quantities
7
Part of a circle's circumference
9
Mathematical rule or equation